The pioneering scientific endeavor of the first Colombian modern astronomer Jos\'e Mar\'ia Gonz\'alez Benito (1843-1903)

Astronomical interest within the current Colombian territory has its roots in the Botanical Expedition of the New Kingdom of Granada, which stimulated the creation of an astronomical observatory in 1803, the first one established in the New World to pursue systematic observations and meteorological studies. After the death in 1816 of its first director, Francisco Jos\'e de Caldas, during the convulsive independence period, no major astronomical observations were made for decades, with few exceptions. In this work we delve into the contributions of the astronomer Jos\'e Mar\'ia Gonz\'alez Benito, the main reactivator of the National Astronomical Observatory of Colombia in the second half of the 19th century, pointing out his pioneering efforts that put worldwide attention to it, and to his own private observatory making him one of the most committed figures to the development of astronomical sciences in the country and the most renowned Colombian in the international astronomical research scene of his time.Comment: 41 pages, 16 figures, 4 tables. Submitted to the Journal for the History of Astronom

Analysis of large-scale photospheric dynamics during the solar cycle 24.

The analysis of the movements of the solar photosphere has been used by several authors to study the dynamics of solar plasma at various spatial and temporal scales. This work, in particular, is focused on the study of vertical movements, in order to perform a statistical analysis of the flow maps to characterize some dynamic aspects of the photospheric plasma along the time evolution of the Sun. To carry out this analysis, we used a set of images obtained by the HMI instrument HMI (Helioseismic and Magnetic Imager) aboard the SDO mission (Solar Dynamics Observatory) to which local correlation tracking algorithms (LCT) were applied. they allow the identification of areas of convergence and divergence of the plasma at certain time intervals during the solar cycle 24, thus covering moments of high and low solar activity. The study gives us the reason for the meridional movements showing that in low latitudes the outgoing emergency flow occupied a higher percentage of area, while in the latitudes near the poles the behavior changes, that is, the incoming flows occupy a greater area.The analysis of the movements of the solar photosphere has been used by several authors to study the dynamics of solar plasma at various spatial and temporal scales. This work, in particular, is focused on the study of vertical movements, in order to perform a statistical analysis of the flow maps to characterize some dynamic aspects of the photospheric plasma along the time evolution of the Sun. To carry out this analysis, we used a set of images obtained by the HMI instrument HMI (Helioseismic and Magnetic Imager) aboard the SDO mission (Solar Dynamics Observatory) to which local correlation tracking algorithms (LCT) were applied. they allow the identification of areas of convergence and divergence of the plasma at certain time intervals during the solar cycle 24, thus covering moments of high and low solar activity. The study gives us the reason for the meridional movements showing that in low latitudes the outgoing emergency flow occupied a higher percentage of area, while in the latitudes near the poles the behavior changes, that is, the incoming flows occupy a greater area

Analysis of large-scale photospheric dynamics during the solar cycle 24.

The analysis of the movements of the solar photosphere has been used by several authors to study the dynamics of solar plasma at various spatial and temporal scales. This work, in particular, is focused on the study of vertical movements, in order to perform a statistical analysis of the flow maps to characterize some dynamic aspects of the photospheric plasma along the time evolution of the Sun. To carry out this analysis, we used a set of images obtained by the HMI instrument HMI (Helioseismic and Magnetic Imager) aboard the SDO mission (Solar Dynamics Observatory) to which local correlation tracking algorithms (LCT) were applied. they allow the identification of areas of convergence and divergence of the plasma at certain time intervals during the solar cycle 24, thus covering moments of high and low solar activity. The study gives us the reason for the meridional movements showing that in low latitudes the outgoing emergency flow occupied a higher percentage of area, while in the latitudes near the poles the behavior changes, that is, the incoming flows occupy a greater area.The analysis of the movements of the solar photosphere has been used by several authors to study the dynamics of solar plasma at various spatial and temporal scales. This work, in particular, is focused on the study of vertical movements, in order to perform a statistical analysis of the flow maps to characterize some dynamic aspects of the photospheric plasma along the time evolution of the Sun. To carry out this analysis, we used a set of images obtained by the HMI instrument HMI (Helioseismic and Magnetic Imager) aboard the SDO mission (Solar Dynamics Observatory) to which local correlation tracking algorithms (LCT) were applied. they allow the identification of areas of convergence and divergence of the plasma at certain time intervals during the solar cycle 24, thus covering moments of high and low solar activity. The study gives us the reason for the meridional movements showing that in low latitudes the outgoing emergency flow occupied a higher percentage of area, while in the latitudes near the poles the behavior changes, that is, the incoming flows occupy a greater area

Analysis of large-scale photospheric dynamics during the solar cycle 24.

The analysis of the movements of the solar photosphere has been used by several authors to study the dynamics of solar plasma at various spatial and temporal scales. This work, in particular, is focused on the study of vertical movements, in order to perform a statistical analysis of the flow maps to characterize some dynamic aspects of the photospheric plasma along the time evolution of the Sun. To carry out this analysis, we used a set of images obtained by the HMI instrument HMI (Helioseismic and Magnetic Imager) aboard the SDO mission (Solar Dynamics Observatory) to which local correlation tracking algorithms (LCT) were applied. they allow the identification of areas of convergence and divergence of the plasma at certain time intervals during the solar cycle 24, thus covering moments of high and low solar activity. The study gives us the reason for the meridional movements showing that in low latitudes the outgoing emergency flow occupied a higher percentage of area, while in the latitudes near the poles the behavior changes, that is, the incoming flows occupy a greater area.The analysis of the movements of the solar photosphere has been used by several authors to study the dynamics of solar plasma at various spatial and temporal scales. This work, in particular, is focused on the study of vertical movements, in order to perform a statistical analysis of the flow maps to characterize some dynamic aspects of the photospheric plasma along the time evolution of the Sun. To carry out this analysis, we used a set of images obtained by the HMI instrument HMI (Helioseismic and Magnetic Imager) aboard the SDO mission (Solar Dynamics Observatory) to which local correlation tracking algorithms (LCT) were applied. they allow the identification of areas of convergence and divergence of the plasma at certain time intervals during the solar cycle 24, thus covering moments of high and low solar activity. The study gives us the reason for the meridional movements showing that in low latitudes the outgoing emergency flow occupied a higher percentage of area, while in the latitudes near the poles the behavior changes, that is, the incoming flows occupy a greater area

Tuning up Fuzzy Inference Systems by using optimization algorithms for the classification of solar flares

In this work we describe the implementation and analysis of different optimization algorithms used for finding the best set of parameters for a Fuzzy Inference System intended to classify solar flares. The parameters will be identified among a universe of possible solutions for the algorithms, and the system will be tested in the particular case of dealing with the aim of classifying the solar flares.Comment: 14 pages, 2 figures, 18 tables. Accepted for publication in TECCIENCI

Illuminating the threat: a decade-long analysis of light pollution in major Colombian urban centres using satellite imagery

La contaminación lumínica es una forma de degradación ambiental que aumenta cada vez más en todo el mundo y afecta el entorno natural, la flora, la fauna y varios aspectos de la vida humana. A pesar de la creciente preocupación por esta problemática, en Colombia su estudio es aún muy limitado. Aquí analizamos de forma exhaustiva la expansión de la luz nocturna artificial en las principales ciudades de Colombia entre el 2012 y el 2022. Se evidenció así un aumento en los niveles de contaminación lumínica en las áreas urbanas de Bogotá, Barranquilla y Cartagena, en tanto que en las de Medellín, Cali y Bucaramanga disminuyó la radiancia promedio. Sin embargo, en todas las ciudades consideradas en el estudio la cobertura de áreas iluminadas aumentó, con un evidente incremento espacial del fenómeno. En el caso de Bogotá, se analizó detalladamente el fenómeno a nivel de localidades y, a partir de datos externos, se verificaron, además, las relaciones del aumento de la contaminación lumínica con la instalación de nuevas luminarias, el cambio a tecnologías LED, y el crecimiento de la densidad poblacional y el producto interno bruto de la ciudad.Light pollution is a form of environmental degradation present throughout the world that affects the natural environment, flora, fauna, and various aspects of human life. Despite the growing concern about this problem, its study in Colombia is still minimal. Here we present a comprehensive analysis of the expansion of artificial nighttime lighting in the main Colombian cities between 2012 and 2022. According to the analysis, light pollution levels in the urban areas of Bogotá, Barranquilla, and Cartagena increased, while in Medellín, Cali, and Bucaramanga, they decreased. However, all the cities evaluated experienced an expansion in the coverage of illuminated areas revealing an evident spatial increase of the problem. In the case of Bogotá, the phenomenon was studied at the locality level. Additionally, we used external data to analyze the relationship between increased light pollution and the installation of new luminaires, the change to LED technologies, and the growing population density and gross domestic product (GDP) in the city. Our results provide valuable information on the threat of light pollution in Colombia and the need to take measures to help control the associated environmental degradation

Energy transport during 3D small-scale reconnection driven by anisotropic plasma turbulence

Energy dissipation in collisionless plasmas is a longstanding fundamental physics problem. Although it is well known that magnetic reconnection and turbulence are coupled and transport energy from system-size scales to sub-proton scales, the details of the energy distribution and energy dissipation channels remain poorly understood. Especially, the energy transfer and transport associated with three dimensional (3D) small-scale reconnection that occurs as a consequence of a turbulent cascade is unknown. We use an explicit fully kinetic particle-in-cell code to simulate 3D small scale magnetic reconnection events forming in anisotropic and Alfv\'enic decaying turbulence. We identify a highly dynamic and asymmetric reconnection event that involves two reconnecting flux ropes. We use a two-fluid approach based on the Boltzmann equation to study the spatial energy transfer associated with the reconnection event and compare the power density terms in the two-fluid energy equations with standard energy-based damping, heating and dissipation proxies. Our findings suggest that the electron bulk flow transports thermal energy density more efficiently than kinetic energy density. Moreover, in our turbulent reconnection event, the energy-density transfer is dominated by plasma compression. This is consistent with turbulent current sheets and turbulent reconnection events, but not with laminar reconnection.Comment: Accepted for publication in Ap

Three-dimensional magnetic reconnection in particle-in-cell simulations of anisotropic plasma turbulence

We use three-dimensional (3-D) fully kinetic particle-in-cell simulations to study the occurrence of magnetic reconnection in a simulation of decaying turbulence created by anisotropic counter-propagating low-frequency Alfvén waves consistent with critical-balance theory. We observe the formation of small-scale current-density structures such as current filaments and current sheets as well as the formation of magnetic flux ropes as part of the turbulent cascade. The large magnetic structures present in the simulation domain retain the initial anisotropy while the small-scale structures produced by the turbulent cascade are less anisotropic. To quantify the occurrence of reconnection in our simulation domain, we develop a new set of indicators based on intensity thresholds to identify reconnection events in which both ions and electrons are heated and accelerated in 3-D particle-in-cell simulations. According to the application of these indicators, we identify the occurrence of reconnection events in the simulation domain and analyse one of these events in detail. The event is related to the reconnection of two flux ropes, and the associated ion and electron exhausts exhibit a complex 3-D structure. We study the profiles of plasma and magnetic-field fluctuations recorded along artificial-spacecraft trajectories passing near and through the reconnection region. Our results suggest the presence of particle heating and acceleration related to small-scale reconnection events within magnetic flux ropes produced by the anisotropic Alfvénic turbulent cascade in the solar wind. These events are related to current structures of the order of a few ion inertial lengths in size

Energy Transport during 3D Small-scale Reconnection Driven by Anisotropic Plasma Turbulence

Abstract: Energy dissipation in collisionless plasmas is a long-standing fundamental physics problem. Although it is well known that magnetic reconnection and turbulence are coupled and transport energy from system-size scales to subproton scales, the details of the energy distribution and energy dissipation channels remain poorly understood. Especially, the energy transfer and transport associated with 3D small-scale reconnection that occurs as a consequence of a turbulent cascade is unknown. We use an explicit fully kinetic particle-in-cell code to simulate 3D small-scale magnetic reconnection events forming in anisotropic and decaying Alfvénic turbulence. We identify a highly dynamic and asymmetric reconnection event that involves two reconnecting flux ropes. We use a two-fluid approach based on the Boltzmann equation to study the spatial energy transfer associated with the reconnection event and compare the power density terms in the two-fluid energy equations with standard energy-based damping, heating, and dissipation proxies. Our findings suggest that the electron bulk flow transports thermal energy density more efficiently than kinetic energy density. Moreover, in our turbulent reconnection event, the energy density transfer is dominated by plasma compression. This is consistent with turbulent current sheets and turbulent reconnection events, but not with laminar reconnection

Plan de formación inicial en habilidades docentes para el profesorado de la Facultad de Educación

Memoria ID-0088. Ayudas de la Universidad de Salamanca para la innovación docente, curso 2017-2018